Field of the Invention
High-yielding cows in modern farming systems live under conditions that are characterised by a very high milk production (dairy cows) or growth rate (beef cattle), which is followed by an equally high energy requirement. The utilisation of the feed decreases markedly when intake is increased beyond maintenance levels. In part to account for this, more and more easily degradable feed is included into the ruminant feed e.g. starch-containing raw materials such a cereal-based concentrates and whole cereal silages. The starchy material is frequently recovered in the faeces implying that the utilisation of such feed ingredients could be enhanced further.
The present invention relates to the use of a bacterial amylase in feed for bovine animals such as dairy cows and beef cattle, in particular for improving milk yield, weight gain, apparent digestibility, disappearance of feedstuff dry matter using the nylon bag method, and/or feed conversion. The invention also relates to compositions such as feed and feed additives comprising the bacterial amylase, as well as methods of preparing such compositions.
Description of the Related Art
WO 03/068256 A1 describes an amylase feed supplement for improved ruminant nutrition. The amylase used is a fungal amylase produced by Aspergillus oryzae. Tricarico et al, in Animal Science 2005, 81: 365-374, describe the effects of Aspergillus oryzae extract containing alpha-amylase activity on ruminal fermentation and milk production in lactating Holstein cows.
U.S. Pat. No. 3,250,622 discloses the use of a specific additive containing proteolytic and amylolytic enzymes as well as gumase, intimately associated with a ground malt carrier, for stimulating milk production in dairy cows. The enzyme source is not specified.
Mora-Jaimes et al (Agrociencia 36(1) (2002), 31-39) studied the performance and ruminal fermentation in lambs fed sorghum grain treated with amylases.
Rojo et al (Animal Feed Science and Technology, 123-124 (2005), 655-665) studied the effects of exogenous amylases from Bacillus licheniformis and Aspergillus niger on ruminal starch digestion and lamb performance.
WO 01/41795 A1 relates to the use of a combination of a protease and an inner salt of a quaternary amine carboxylic acid in the treatment and/or prophylaxis of coccidiosis and bacterial infections. An improved weight gain of animals in general is also claimed. A xylanase and/or an amylase may be included. Alpha-amylase from Bacillus subtilis is mentioned. Ruminants are also mentioned, however all examples relate to broiler chicks.
It is an object of the present invention to provide alternative, preferably improved, amylases which may alleviate the problems described above by improving feed utilization, milk yield, and/or weight gain. The amylases of the invention furthermore, or in the alternative, may have improved properties such as dose-response profile, pH-profile, pelleting-stability, temperature-stability, bile-salt stability, protease-stability, and/or specific activity. The amylases of the invention may furthermore, or in the alternative, be capable of degrading starch in the rumen, in the large intestines, and/or in the small intestines.